import React from "react";

export default class Form extends React.Component {
    state={
        username:'lal'
    }
  onUsernameChange = (e) => {
    console.log(e.target.value);
    this.setState({ username: e.target.value });
  };

  render() {
    return (
      <from>
        <input type="text" onChange={this.onUsernameChange} placeholder="用户输入" />
        <input type="submit" value="Submit" />
      </from>
    );
  }
}
